ABSTRACT Spinocerebellar ataxia type 6 (SCA6) is an incurable hereditary degenerative ataxic disease passed from parent to child. We have developed a novel, microRNA-based gene therapy approach to inhibit expression the disease-causing protein, alpha1ACT made by the gene CACNA1A. This approach, which relies on an adenovirus to deliver the micro RNA, spares the other critical CACNA1A protein, alpha1A calcium channel subunit, although it appears to suppress both the disease-causing and normal alpha1ACT proteins. Here in Aim 1 we propose to expand on our initial study that inhibited a hyper acute neonatal mouse of SCA6 by comparing two different routes (intraventricular and intravenous) of administration of the adenovirus- microRNA, for effectiveness in blocking the hyperacute mouse model and a new BAC-based transgenic mouse model. In Aim 2 we will use a mouse CACNA1A mutant and a novel transgenic mouse model expressing normal alpha1ACT to prove that suppression of normal alpha1ACT is safe in adult mice, paving the way to safely envision a similar approach in patients with SCA6.